ABSTRACT
The somatic sensory—or somatosensory— system is a group of sensory submodalities that convey and interpret sensory information originating in the skin and muscles. The skin accomplishes many sensory functions—thus the term “cutaneous sensation.” Touch, temperature, pressure, vibration sensations, and superficial pain are carried out by sensory processes located in the skin. The details of how the stimuli for the various receptors of the somatic sensory system produce a depolarization that ultimately triggers the action potential are poorly understood in most individual somatic sensory receptors except for the Pacinian corpuscle. The neural codes that the somatic sensory receptors use are similar to other sensory systems: the frequency code and the population code. The intensity of the stimulus is coded by a frequency code: the neural fiber attached to the individual receptors fires more quickly in proportion to the intensity of the stimulus.
